Objective: To investigate the role of expression of matrix metallo-proteinase 14 (MMP14) in laryngeal carcinomas and the relationship between MMP14 expression and the laryngeal biological behavior.
Methods: The gene expression differences of MMP14 between fresh laryngeal cancer tissues and their surrounding normal mucosa was analyzed by RT-PCR. The expression of MMP14 protein in paraffin-embedded tissues was determined immunohistochemically. All statistical analyses were performed by SPSS version 10.0.
Results: In the 33 cases of matched specimens, MMP14 gene expression was much higher in tumor tissues than that in surrounding ing normal tissues in 26 cases and lower in 2 cases, whereas in other 5 cases, no significant difference was observed between the cancer tissue and the surrounding normal tissue. MMP14 gene expression was not different in different stages in laryngeal glottic cancers, but correlated to the differentiation and lymph node metastasis (P < 0.05). There was correlation between MMP14 gene expression and the stage, differentiation and lymph node metastasis in the laryngeal supraglottic cancers (P < .05). MMP14 protein was localized predominantly in the carcinoma cell cytoplasm and in the stromal fibroblast cytoplasm, and weakly or not expressed in surrounding normal tissue. MMP14 protein expression was much higher in tumor tissue than that in surrounding normal tissue in most of the cases. In general, MMP14 protein expression was the same as MMP14 gene expression and related to the stage, differentiation and lymph node metastasis in the laryngeal cancers. There was no survival difference at 3, 5 and 7-year between the group with higher MMP14 protein expression in tumor tissues than surrounding normal tissues and the group with no difference of MMP14 protein expression (Log Rank, P=0.5535).
Conclusions: The protein MMP14 may play role in laryngeal cancer invasion in a certain extent, but important role in lymph node metastasis of laryngeal cancer. The over-expression of MMP14 protein may be a marker for lymph node metastasis of laryngeal cancer.